The use of several antennas integrated with a metal housing, in a multimedia system or an automobile radio for example, is known from the prior art. In particular, numerous automotive vehicles comprise multimedia systems comprising a metal housing encasing several antennas, working in various frequency bands, to allow Bluetooth® communications in the band 2.400 GHz-2.485 GHz and Wifi® communications in the two bands 2.400 GHz-2.485 GHz and 5.00 GHz-5.85 GHz, within the cabin of the vehicle, or else to receive satellite navigation signals in particular.
Thus, it is known from the prior art that antennas are designed to be integrated with metal housings of multimedia systems, themselves integrated with central consoles in automotive vehicle cabins, said antennas being configured to emit in frequency bands such as the band 2.400 GHz-2.485 GHz or else the band 5.00 GHz-5.85 GHz.
In such a context, it is obvious that the mechanical characteristics, such as the shape and the arrangement of the metal housing, have a significant impact on the performance of said antennas.
In the known devices, the performance of such antennas is thus seriously altered with respect to what it would be in a context where said antennas were not integrated into a metal housing and thus-confined.
The mechanical environment of such multi-band antennas indeed gives rise to a strong impact on their performance, reducing in particular their performance in terms of matching, gain, radiation, etc.
Generally, the prior art discloses various methodologies for designing antennas, miniature antennas especially, and in particular exhibiting multi-band emission/reception characteristics.
However, no satisfactory solution is known as regards the optimization of the performance of multi-band antennas intended to be enclosed in metal housings, such as automotive vehicle multimedia systems.
Moreover, the use of a plurality of antennas, in particular of at least two antennas, in such a context, renders yet more complex the analysis aimed at determining the best arrangement to obtain the best compromise in terms of performance of said antennas. In practice, the only known solutions consist in placing such antennas in a housing environment exhibiting fewer metal parts and a maximum of free volume. Nonetheless, metal parts acting as screen still remain and the volume available for the antennas is still limited, so that multi-antenna devices integrated with metal housings in multimedia systems exhibit, in the prior art, degraded performance.